bug#70628: segmentation fault reading socketpair after fork
Jakov Tutavac <[email protected]>
| Newsgroups | gmane.lisp.guile.bugs |
|---|---|
| Message-ID | <CAA2KzJdpT=nYwLcHRqpVGaQs_8K9e-xFP-vfnS7B0bdR8KdOjg@mail.gmail.com> |
Dear Sir/Madam, The 62 lines of code in the attachment result in a segmentation fault when run. I hope you can help suggest a fix or a workaround. user@pcxy:~/$ guile --version guile (GNU Guile) 3.0.7 Packaged by Debian (3.0.7-deb+3.0.7-1) user@pcxy:~/$ make gcc -I/usr/include/guile/3.0 -g -c -o main.o main.c gcc -o a.out main.o -lguile-3.0 -lgc -lpthread -ldl user@pcxy:~/$ ./a.out Parent sv:3 Child sv:4 Segmentation fault (core dumped) (gdb) r Starting program: a.out [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [Detaching after fork from child process 100100] Parent sv:3 Program received signal SIGSEGV, Segmentation fault. 0x00007ffff7be68f2 in GC_find_limit_with_bound () from /lib/x86_64-linux-gnu/libgc.so.1
main.c
(text/x-csrc, 1.2 KB)
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <fcntl.h>
#include <libguile.h>
static void *main_parent(void *arg)
{
int sv = *((int *) arg);
SCM port;
char *buf = "Write from parent\n";
printf("Parent sv:%d\n", sv);
port = scm_fdopen(scm_from_int(dup(sv)), scm_from_utf8_stringn("r+", 2));
scm_c_write(port, buf, sizeof(buf));
}
static void *main_child(void *arg)
{
int sv = *((int *) arg);
SCM port;
char *buf = " \n";
printf("Child sv:%d\n", sv);
port = scm_fdopen(scm_from_int(dup(sv)), scm_from_utf8_stringn("r+", 2));
scm_c_read(port, buf, sizeof(buf));
printf("%s\n", buf);
}
int main(int argc, char *argv[])
{
pid_t id;
int sv[2];
if (socketpair(AF_UNIX, SOCK_DGRAM, 0, sv) != 0) {
fprintf(stderr, "%s", strerror(errno));
return EXIT_FAILURE;
}
id = fork();
if (id == -1) {
fprintf(stderr, "%s", strerror(errno));
return EXIT_FAILURE;
}
if (id == 0) {
/* parent process */
scm_with_guile(main_parent, &sv[0]);
} else {
/* child process */
scm_with_guile(main_child, &sv[1]);
}
wait(NULL);
return EXIT_SUCCESS;
}